Bridget Henry didn't think her school, the University of Iowa, gave students an appropriate venue to participate in the search for a new president. That's why Ms. Henry, a senior majoring in political science, started "Hogan's Heroes," a group supporting provost Michael Hogan for the job.

Henry and her friends tried a laundry list of ways to publicize "Hogan's Heroes" – everything from a letter-writing campaign to handing out flyers. But what succeeded most was their page on the social networking website Facebook, which attracted more than 200 supporters.

Even if Hogan doesn't get the job, Henry learned what colleges and universities are waking up to: Facebook is no longer just a fun way for students to keep in touch. It is now essential to the college experience, a fact that faculty and staff are scurrying to catch up with.

Soon to enter its fourth year, Facebook has matured into a warehouse of school information, a big-time player in campus activism, and a mirror of university life – good and bad. More than 12 million users are signed up.

School officials, most of whom were either dismissive or unaware of the phenomenon, are now awake to it. They hold Facebook-themed conferences. They sign up themselves. They monitor students. And they worry about information in student profiles, especially after hearing that employers routinely check them.

What do students do on Facebook? A lot.

Students still "friend" others in their school or regional networks, exchange messages and pictures (Facebook claims to be the largest photo-sharing website), check class schedules, or post diary notes.

Then there are groups like Henry's, for example. Or the one at Tufts University in Medford, Mass., that wants to revive sluggish campus social life. Hundreds of groups are out to ban something, from horse slaughter to button-fly jeans. The mother of all groups, started by Northwestern University student Ben Parr in September, has 450,000 people – 100,000 of which joined the first day. They made Facebook change an unpopular newsfeed feature that listed any change your friends made to their profiles. Campus organizations use Facebook, not fliers, to advertise membership and events.

Students running for campus office campaign on Facebook, as do actual politicians. Any candidate paying attention to youth was on Facebook for the November elections. Their staffs target students based on the political preferences they list.

Facebook also hosts the bad: sexual and racial harassment, hazing, extortion, and threats. School officials, even campus police, use the site to investigate.

"Any [campus] behavior that you could experience face to face, you'll see on Facebook," says Pablo Malavenda, associate dean of students at Purdue University in West Lafayette, Ind. Mr. Malavenda created his profile in January 2005 and now has more than 700 friends. His early knowledge of the phenomenon made his school less reactive. As Facebook picked up steam, Kent State University in Kent, Ohio, banned its athletes from using it. The University of New Mexico banned it outright for months. Malavenda says the schools overreacted because they were confused – after all, he adds, social networking is the biggest campus phenomenon since phones were allowed in residence halls.

Malavenda knows dozens of Facebook stories: relationships that ended when one partner read the other's "wall" and realized that he or she was seeing others; the student who didn't get a job because their Facebook profile presented them as the next big thing in binge drinking.

There's his own story, too. Last fall, Malavenda caught a group of students selling cocaine and kicked them off campus. In response, they started a Facebook group called "We hate Pablo," complete with directions to his house and instructions to hurt and eliminate him.

"I signed up for this job with everything that comes with it," Malavenda says. "But my kids haven't. My wife hasn't."

Malavenda got the police involved. The students were put on academic suspension for five years. But he doesn't blame Facebook. "The behavior is what you deal with, not where it occurred," he says. It also doesn't hurt that a "We Love Pablo" group formed in response – something Malavenda says is "quite enjoyable."

Educating students about Facebook is a priority now, and the bulk of the efforts originate in the Student Affairs or IT departments. Brian Payst, director of technology at the University of North Carolina-Chapel Hill, says schools need to use the changing ways in which students communicate. While Facebook orientation and policy documents are now common on campuses, some schools have gotten more creative. Mr. Payst and his team created two dummy profiles to illustrate the perils of excessive self-revelation. "Ivana Bea Stalked" posts her address, cellphone number, and writes of her recent piercings and wearing her favorite red underwear. "Lloyed Unemployed" brags about doing nothing and hopes to find a job that pays him to drink beer.

"We have to be flexible and try some different stuff," Payst says. "We'll have a better chance of getting the message to work."

At the University of Missouri-Columbia, Facebook and MySpace, another popular social-networking site, are addressed in a skit performed several times during summer welcome events. At Cornell University in Ithaca, N.Y., Tracy Mitrano, director of IT policy, wrote "Thoughts on Facebook," a nonacademic sounding document widely circulated among colleges.

"Trying to get a deal on car insurance?" it reads in part. "Who knows, maybe that little Geico went to Cornell! Do you really want him seeing a photograph of you bombed out of your mind?"

At Mercyhurst College in Erie, Pa., administrators sent "a call to action," asking faculty and staff to join Facebook in the hopes that it would have a "norming influence" on content. Joseph Howard, assistant director of residence life, says it seems to be working, as the school's Facebook network is now a "virtual Mercyhurst."

Not everyone embraces Facebook. Michael Bugeja, director of the journalism school at Iowa State University, views Facebook as one of several distractions that the spread of wireless access has allowed to flourish on campuses. Mr. Bugeja, who researched interaction with technology for his book "The Interpersonal Divide," says it's important that administrators keep tabs not only on the virtual world, but also the physical world, checking on where, and for how long, students access Facebook. "Technology is never a single phenomenon," Bugeja says. "You're in the physical world and the virtual world. We continue to believe technology advances the senses. But no, it splits the senses."

Bugeja says he is not a technophobe, but he worries that technology will undermine the teaching of critical thinking. "Facebook is a fine vehicle to organize a celebration or a protest, to inform users about schedules and events and it can facilitate real friendships," he says. "But those are the exceptions, not the rule."

Facebook seems to fly in the face of the short life expectancy of Internet phenomena. It's not growing at the same pace it did – but only because almost every student in the US is on it. New freshmen sign on every year. "They have dominated their niche," says Fred Stutzman, who studies Facebook for his doctoral dissertation at UNC. "No one even competes."

Unless Facebook shoots itself in the foot, it's here for the foreseeable future. Its major test will be the sale of the site, which many expect to happen in the next six to 12 months. Mr. Stutzman wouldn't be surprised to see a price of $1 billion. The questions are, who will buy it and why? And how will they make money from it?

Some scenarios are troubling. "Facebook is this incredible data-mining project," Stutzman says. The site owns the demographic information, interests, and social networks of millions – a dream for data lovers from advertisers to government agencies.

"That data," he says, "is worth so much more than [anyone] would pay for Facebook."

A brief history of Facebook

February 2004: Mark Zuckerberg launches Facebook at Harvard University with the aim of replacing traditional printed face books, which have photos and short bios of incoming students. The site is a hit, and within a few months it expands to other schools in the area.

December 2004: By this time, Zuckerberg had dropped out of Harvard and opened an office in Palo Alto, Calif., with a staff of eight. Facebook has about 1 million users.

Summer 2005: Most American universities have a Facebook network.

Fall 2005: Facebook expands to allow high school students to join.

December 2005: Facebook has expanded to universities in Britain, Canada, and Australia, among others. Estimated users: 11 million.

September 2006: Facebook opens registration to all Internet users. Rumors of purchase offers from Google and Yahoo begin to circulate. Estimated users: 12 million plus.

Sources: Facebook.com, Wikipedia

Should employers check job candidates on Facebook? Most students say no.

One of the most publicized warnings about Facebook comes from a slew of surveys showing that employers check Facebook profiles before making hiring decisions. This is where that picture of a student passed out next to a bed with toothpaste smeared on his face is least likely to elicit grudging admiration. Many such pictures exist on Facebook.

A recent survey by Christine Wiley and Mark Sisson, who work in the Career Services office at the University of Dayton, Ohio, not only confirms the use of Facebook by employers, but it also points to the disconnect that exists between students and the adults who make decisions about them.

The researchers polled 2,000 students at colleges in the Dayton area and more than 300 employers. They found that 40 percent of employers say it's OK to use Facebook when making a hiring decision; only 19 percent of the students agreed. Sixty percent of the students said employers should not consider a Facebook entry.

A slightly differently worded question underscored the difference in perception of Facebook.

Thirty-two percent of students said employers' use of Facebook is illegal; 42 percent said it's a violation of privacy.

Employers disagreed. Only one-quarter of them considered it unethical; 21 percent said it was a violation of privacy.

The researchers say the reason for this perception gap is most likely generational.

Such surveys are making students more careful of what they put in their profiles. Melissa Bush, a senior at the University of Dayton, works for the school's Career Services office. She uses the "grandma test" for the information she puts on Facebook.